Yes, I attended a meeting in downtown LA last week, and took the Metrolink train and MTA Red line, which connects underneath LA's Union Station. The round trip fare was $12, and that covers the Red Line transfer. Getting from the Anaheim Amtrak/Metrolink station to the DL area is another question of course. There's an OCTA bus that runs east and west on Katella, but the bus stop is on the NW corner of State College and Katella, which is a bit of a hike (15-20 minutes I'll guess). You might just want to take a taxi from the train station.